What is sg-551?

SG-551 is a 5.56x45mm NATO calibre assault rifle that was developed by Swiss Arms in Switzerland in the early 1990s. It is an improved version of the SG-550 model and is known for its reliability, accuracy, and durability. The SG-551 has a modular design that allows for easy customization and maintenance. It features a gas piston system, a folding stock, and a full-length Picatinny rail on the top of the receiver, allowing for the attachment of various optical sights and accessories. The barrel length of the SG-551 is 363mm, and it weighs around 3.4 kg. It is commonly used by several military and law enforcement agencies around the world.